Most replayed moment: How to stop fighting your body clock | Prof. Debra Skene

SPEAKER_1 (0:01)

Hello, and welcome to ZOE Recap, where each week, we find the best bits from one of our podcast episodes to help you improve your health. Every one of us runs on a biological rhythm, a finely tuned system that controls when we feel alert, when we feel tired, and even how we process food. But here's the problem. Modern life doesn't always respect this rhythm. Late nights, early alarms, and irregular meals put many of us out of sync with our own biology. I'm joined by Professor Debra Skene to explain why this mismatch matters and how you can transform your health by aligning your lifestyle with your internal ticker.

One of the biggest purposes of this biological clock is actually to separate the times when you're eating and the times when you're not, so that your body is prepared to deal with the influx of everything that comes from the food and then have a period when you're not.

Debra Skene (1:00)

When you're fasting.

SPEAKER_1 (1:01)

And therefore if you are eating suddenly like in the middle of the night when I'm not expecting to it, actually your body isn't prepared and that has some quite big negative health impacts?

Debra Skene (1:10)

Yes, so we think and then over time because this, let's say this increase in fats at night based on the food you eat, if that accumulates over time, this could be one of the explanations. Once we knew the epidemiology showing this increased risk of these disorders, particularly metabolic disorders, cardiovascular problems and cancer, people have really tried to go, well, what is the contributing factor? And so you get all these diagrams of light at night, eating food at night, mismatch of clocks, etc.

So that it all then funnels down into maybe this is increasing the risk. But as I say, the precise mechanisms are not known. And what's the hierarchy of these things? Is it because you've shifted your sleep-wake timing?

Is that the thing that's the most disruptive for disease? Or is it the fact that you've shifted your feeding fasting, for example? So we don't know that yet. If we know that, then we can start giving advice to shift workers and advice to people who employ shift workers.

SPEAKER_1 (2:30)

You're saying the thing that is causing most of the problem, it's not that I might be awake during the night and not seen as much sunlight. It's the fact that my body clock is out of line with how I'm living. You know, if I was going to live in a cave for a month, I'm not having the same risk as I am sort of shifting between day and night time and my body clock moving around.

Debra Skene (2:55)

Living in a cave for a month is pretty healthy, because you would be just going to your own time. So you would then be living according to your body clock timing. And this, in theory, is the most healthy thing to do.

The problem we have is that we have a social clock that's set on our wrists here. Chronobiologists don't wear watches, because we don't need a social clock to tell us what the time is. We've got our body clocks. But anyway, that social clock is telling you, please wake up, please go to work, please go to school. And this can be in conflict with our body clock. And it is.

And this is where we get this thing of the speeds of people's clocks. Now we get clocks that are slow, and we get clocks that are fast. And people who have slow clocks are more evening types, or hours, you know, late types. And people who have fast clocks are more morning types, or what we call locks. And they all have to fit into this sort of nine to five program that we have. And so some people are really living against their biological clock system. You know, if you're a late type, and you're being forced to wake up at six o'clock in the morning to go to work, this is a big jaw and a mismatch that does eventually have some health consequences.

SPEAKER_1 (4:38)

My next biggest set of questions, we're all around meal timing. And I understand you've recently been studying this. So what is the advice you can give us?

Debra Skene (4:47)

Everybody has focused for so long on what you should eat, but it's now about when and is there a correct or appropriate timing of food? And there are bigger experts than me at this, but we've done some very controlled lab studies where the question has been, okay, let's shift the whole meal schedule by five hours. So that would be breakfast, lunch and dinner moved five hours. And then what happens to our body clocks?